Piwik install : Table 'bdd.prefix_site' doesn't exist

I have some difficulties when installing Piwik on my website
The following message is displayed after the 3rd step (database setp up) :

Mysqli prepare error: Table ‘tenniscltbtcf.xehp1_site’ doesn’t exist

I’ve checked my database and this table does not exist. Well !!!

How this table should be created ? Is it part of the piwik installation process or should it be created by my website ?

Any idea to resolve this issue ?

Thanks for your support

My Configuration :
Piwik 1.10.1
remote server : OVH
Website generated with Joomla 2.5

Can you delete all tables and try again ?

If all table are deleted, i will lose all my website data?